A latching mechanism for a tool spindle or mandrel that latches by pivotally extending a plurality of tensioned arms from a tensioned seated state to a tensioned locked state through rotation of a lock ring pivotally deploying the arms from their nested seated state into a blade engaging position of a larger radius than the radius of the lock ring with the arms in their nested position.

The invention concerns a shrink-fit chuck (1) for clamping an object, in particular for clamping a milling cutter in a milling machine, having a cylindrical receiving bore (3) for receiving a cylindrical shank of the object to be clamped, the receiving bore (3) extending in the shrink-fit chuck (1) and being bounded on the outside by a wall (4). The shrink-fit chuck (1) according to the invention is characterised by a rib (12) which extends transversely to the longitudinal axis (13) of the receiving bore (3) and projects inwards from the wall (4) of the receiving bore (3) into the receiving bore (3), so that the rib (12) permits the complete insertion of the shank (5) into the receiving bore (3) only in a predetermined angular position of the shank (5).

A latching mechanism for a tool spindle or mandrel that latches by pivotally extending a plurality of tensioned arms from a tensioned seated state to a tensioned locked state through rotation of a lock ring pivotally deploying the arms from their nested seated state into a blade engaging position of a larger radius than the radius of the lock ring with the arms in their nested position.